[PATCH v2 2/2] phy: amlogic: add USB3 PHY support for Meson GXL and GXM
Martin Blumenstingl
martin.blumenstingl at googlemail.com
Sun Jan 28 12:15:54 PST 2018
This adds a new driver for the USB3 PHY found on Meson GXL and GXM SoCs
(both SoCs are using the same USB PHY register layout).
Unfortunately there is no documentation for this PHY in the public S905X
datasheet (published for example by Khadas). What we know so far about
this PHY:
- even though the Meson GXL and GXM SoCs do not expose an USB3 port (the
dwc3 controller only has USB2 ports enabled) we need to initialize the
USB3 PHY (specifically USB_R1_U3H_FLADJ_30MHZ_REG_MASK). Without this
initialization high-speed USB devices (especially USB hard disks and
thumb drives, slower devices like mice do not seem to be affected)
- on some boards the USB3 PHY starts in "device mode" - we want to bring
it into a known state (by switching it to host mode for now).
- it is responsible for the OTG detection and for switching the first
USB2 PHY between host and peripheral (aka device) mode. an interrupt
can be used to detect changes between host and device mode.
There are five inputs to this register area:
- the clock and reset line for the USB3 PHY itself
- the clock and reset line for the peripheral mode and OTG detection
logic (on the GXL and GXM SoCs these are the same clock and reset line
as for the USB3 PHY itself, but Amlogic sees this as two different
components - even though they share the same register space - so they
have to be passed individually to allow specifying different inputs on
other SoCs if needed)
- the interrupt for the OTG detection logic
The whole OTG detection logic is not implemented yet.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>
---
drivers/phy/amlogic/Kconfig | 12 ++
drivers/phy/amlogic/Makefile | 1 +
drivers/phy/amlogic/phy-meson-gxl-usb3.c | 288 +++++++++++++++++++++++++++++++
3 files changed, 301 insertions(+)
create mode 100644 drivers/phy/amlogic/phy-meson-gxl-usb3.c
diff --git a/drivers/phy/amlogic/Kconfig b/drivers/phy/amlogic/Kconfig
index cb8f4501652b..2f690d24203a 100644
--- a/drivers/phy/amlogic/Kconfig
+++ b/drivers/phy/amlogic/Kconfig
@@ -25,3 +25,15 @@ config PHY_MESON_GXL_USB2
Enable this to support the Meson USB2 PHYs found in Meson
GXL and GXM SoCs.
If unsure, say N.
+
+config PHY_MESON_GXL_USB3
+ tristate "Meson GXL and GXM USB3 PHY drivers"
+ default ARCH_MESON
+ depends on OF && (ARCH_MESON || COMPILE_TEST)
+ depends on USB_SUPPORT
+ select GENERIC_PHY
+ select REGMAP_MMIO
+ help
+ Enable this to support the Meson USB3 PHY and OTG detection
+ IP block found in Meson GXL and GXM SoCs.
+ If unsure, say N.
diff --git a/drivers/phy/amlogic/Makefile b/drivers/phy/amlogic/Makefile
index cfdc98715c30..4fd8848c194d 100644
--- a/drivers/phy/amlogic/Makefile
+++ b/drivers/phy/amlogic/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_PHY_MESON8B_USB2) += phy-meson8b-usb2.o
obj-$(CONFIG_PHY_MESON_GXL_USB2) += phy-meson-gxl-usb2.o
+obj-$(CONFIG_PHY_MESON_GXL_USB3) += phy-meson-gxl-usb3.o
diff --git a/drivers/phy/amlogic/phy-meson-gxl-usb3.c b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
new file mode 100644
index 000000000000..f464df679017
--- /dev/null
+++ b/drivers/phy/amlogic/phy-meson-gxl-usb3.c
@@ -0,0 +1,288 @@
+/*
+ * Meson GXL USB3 PHY and OTG mode detection driver
+ *
+ * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl at googlemail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+
+#define USB_R0 0x00
+ #define USB_R0_P30_FSEL_MASK GENMASK(5, 0)
+ #define USB_R0_P30_PHY_RESET BIT(6)
+ #define USB_R0_P30_TEST_POWERDOWN_HSP BIT(7)
+ #define USB_R0_P30_TEST_POWERDOWN_SSP BIT(8)
+ #define USB_R0_P30_ACJT_LEVEL_MASK GENMASK(13, 9)
+ #define USB_R0_P30_TX_BOOST_LEVEL_MASK GENMASK(16, 14)
+ #define USB_R0_P30_LANE0_TX2RX_LOOPBACK BIT(17)
+ #define USB_R0_P30_LANE0_EXT_PCLK_REQ BIT(18)
+ #define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK GENMASK(28, 19)
+ #define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK GENMASK(30, 29)
+ #define USB_R0_U2D_ACT BIT(31)
+
+#define USB_R1 0x04
+ #define USB_R1_U3H_BIGENDIAN_GS BIT(0)
+ #define USB_R1_U3H_PME_ENABLE BIT(1)
+ #define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK GENMASK(6, 2)
+ #define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK GENMASK(11, 7)
+ #define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK GENMASK(15, 12)
+ #define USB_R1_U3H_HOST_U3_PORT_DISABLE BIT(16)
+ #define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT BIT(17)
+ #define USB_R1_U3H_HOST_MSI_ENABLE BIT(18)
+ #define USB_R1_U3H_FLADJ_30MHZ_REG_MASK GENMASK(24, 19)
+ #define USB_R1_P30_PCS_TX_SWING_FULL_MASK GENMASK(31, 25)
+
+#define USB_R2 0x08
+ #define USB_R2_P30_CR_DATA_IN_MASK GENMASK(15, 0)
+ #define USB_R2_P30_CR_READ BIT(16)
+ #define USB_R2_P30_CR_WRITE BIT(17)
+ #define USB_R2_P30_CR_CAP_ADDR BIT(18)
+ #define USB_R2_P30_CR_CAP_DATA BIT(19)
+ #define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK GENMASK(25, 20)
+ #define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK GENMASK(31, 26)
+
+#define USB_R3 0x0c
+ #define USB_R3_P30_SSC_ENABLE BIT(0)
+ #define USB_R3_P30_SSC_RANGE_MASK GENMASK(3, 1)
+ #define USB_R3_P30_SSC_REF_CLK_SEL_MASK GENMASK(12, 4)
+ #define USB_R3_P30_REF_SSP_EN BIT(13)
+ #define USB_R3_P30_LOS_BIAS_MASK GENMASK(18, 16)
+ #define USB_R3_P30_LOS_LEVEL_MASK GENMASK(23, 19)
+ #define USB_R3_P30_MPLL_MULTIPLIER_MASK GENMASK(30, 24)
+
+#define USB_R4 0x10
+ #define USB_R4_P21_PORT_RESET_0 BIT(0)
+ #define USB_R4_P21_SLEEP_M0 BIT(1)
+ #define USB_R4_MEM_PD_MASK GENMASK(3, 2)
+ #define USB_R4_P21_ONLY BIT(4)
+
+#define USB_R5 0x14
+ #define USB_R5_ID_DIG_SYNC BIT(0)
+ #define USB_R5_ID_DIG_REG BIT(1)
+ #define USB_R5_ID_DIG_CFG_MASK GENMASK(3, 2)
+ #define USB_R5_ID_DIG_EN_0 BIT(4)
+ #define USB_R5_ID_DIG_EN_1 BIT(5)
+ #define USB_R5_ID_DIG_CURR BIT(6)
+ #define USB_R5_ID_DIG_IRQ BIT(7)
+ #define USB_R5_ID_DIG_TH_MASK GENMASK(15, 8)
+ #define USB_R5_ID_DIG_CNT_MASK GENMASK(23, 16)
+
+/* read-only register */
+#define USB_R6 0x18
+ #define USB_R6_P30_CR_DATA_OUT_MASK GENMASK(15, 0)
+ #define USB_R6_P30_CR_ACK BIT(16)
+
+struct phy_meson_gxl_usb3_priv {
+ struct regmap *regmap;
+ enum phy_mode mode;
+ struct clk *clk_phy;
+ struct clk *clk_peripheral;
+ struct reset_control *reset;
+};
+
+static const struct regmap_config phy_meson_gxl_usb3_regmap_conf = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = USB_R6,
+};
+
+static int phy_meson_gxl_usb3_power_on(struct phy *phy)
+{
+ struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+ regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0,
+ USB_R5_ID_DIG_EN_0);
+ regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1,
+ USB_R5_ID_DIG_EN_1);
+ regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_TH_MASK,
+ FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
+
+ return 0;
+}
+
+static int phy_meson_gxl_usb3_power_off(struct phy *phy)
+{
+ struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+ regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_0, 0);
+ regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_EN_1, 0);
+
+ return 0;
+}
+
+static int phy_meson_gxl_usb3_set_mode(struct phy *phy, enum phy_mode mode)
+{
+ struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+ switch (mode) {
+ case PHY_MODE_USB_HOST:
+ regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT, 0);
+ regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+ 0);
+ break;
+
+ case PHY_MODE_USB_DEVICE:
+ regmap_update_bits(priv->regmap, USB_R0, USB_R0_U2D_ACT,
+ USB_R0_U2D_ACT);
+ regmap_update_bits(priv->regmap, USB_R4, USB_R4_P21_SLEEP_M0,
+ USB_R4_P21_SLEEP_M0);
+ break;
+
+ default:
+ dev_err(&phy->dev, "unsupported PHY mode %d\n", mode);
+ return -EINVAL;
+ }
+
+ priv->mode = mode;
+
+ return 0;
+}
+
+static int phy_meson_gxl_usb3_init(struct phy *phy)
+{
+ struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+ int ret;
+
+ ret = reset_control_reset(priv->reset);
+ if (ret)
+ goto err;
+
+ ret = clk_prepare_enable(priv->clk_phy);
+ if (ret)
+ goto err;
+
+ ret = clk_prepare_enable(priv->clk_peripheral);
+ if (ret)
+ goto err_disable_clk_phy;
+
+ ret = phy_meson_gxl_usb3_set_mode(phy, priv->mode);
+ if (ret)
+ goto err_disable_clk_peripheral;
+
+ regmap_update_bits(priv->regmap, USB_R1,
+ USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
+ FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
+
+ return 0;
+
+err_disable_clk_peripheral:
+ clk_disable_unprepare(priv->clk_peripheral);
+err_disable_clk_phy:
+ clk_disable_unprepare(priv->clk_phy);
+err:
+ return ret;
+}
+
+static int phy_meson_gxl_usb3_exit(struct phy *phy)
+{
+ struct phy_meson_gxl_usb3_priv *priv = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(priv->clk_peripheral);
+ clk_disable_unprepare(priv->clk_phy);
+
+ return 0;
+}
+
+static const struct phy_ops phy_meson_gxl_usb3_ops = {
+ .power_on = phy_meson_gxl_usb3_power_on,
+ .power_off = phy_meson_gxl_usb3_power_off,
+ .set_mode = phy_meson_gxl_usb3_set_mode,
+ .init = phy_meson_gxl_usb3_init,
+ .exit = phy_meson_gxl_usb3_exit,
+ .owner = THIS_MODULE,
+};
+
+static int phy_meson_gxl_usb3_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct phy_meson_gxl_usb3_priv *priv;
+ struct resource *res;
+ struct phy *phy;
+ struct phy_provider *phy_provider;
+ void __iomem *base;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ priv->regmap = devm_regmap_init_mmio(dev, base,
+ &phy_meson_gxl_usb3_regmap_conf);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ priv->clk_phy = devm_clk_get(dev, "phy");
+ if (IS_ERR(priv->clk_phy))
+ return PTR_ERR(priv->clk_phy);
+
+ priv->clk_peripheral = devm_clk_get(dev, "peripheral");
+ if (IS_ERR(priv->clk_peripheral))
+ return PTR_ERR(priv->clk_peripheral);
+
+ priv->reset = devm_reset_control_array_get_shared(dev);
+ if (IS_ERR(priv->reset))
+ return PTR_ERR(priv->reset);
+
+ /*
+ * default to host mode as hardware defaults and/or boot-loader
+ * behavior can result in this PHY starting up in device mode. this
+ * default and the initialization in phy_meson_gxl_usb3_init ensure
+ * that we reproducibly start in a known mode on all devices.
+ */
+ priv->mode = PHY_MODE_USB_HOST;
+
+ phy = devm_phy_create(dev, np, &phy_meson_gxl_usb3_ops);
+ if (IS_ERR(phy)) {
+ ret = PTR_ERR(phy);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to create PHY\n");
+
+ return ret;
+ }
+
+ phy_set_drvdata(phy, priv);
+
+ phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id phy_meson_gxl_usb3_of_match[] = {
+ { .compatible = "amlogic,meson-gxl-usb3-phy", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb3_of_match);
+
+static struct platform_driver phy_meson_gxl_usb3_driver = {
+ .probe = phy_meson_gxl_usb3_probe,
+ .driver = {
+ .name = "phy-meson-gxl-usb3",
+ .of_match_table = phy_meson_gxl_usb3_of_match,
+ },
+};
+module_platform_driver(phy_meson_gxl_usb3_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl at googlemail.com>");
+MODULE_DESCRIPTION("Meson GXL USB3 PHY and OTG detection driver");
+MODULE_LICENSE("GPL v2");
--
2.16.1
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